They can add a hint of romance to a meal or make taking a bath a real luxury.
But scented candles can be bad for your health, say scientists.
The smoke produced by many of them is laced with toxins linked to cancer, asthma and eczema.
The odd candle is unlikely to do any harm, but we should avoid using them day after day in bathrooms and other poorly ventilated rooms, say the researchers.
The U.S. researchers burnt a range of candles in the laboratory and collected and tested the substances given off.
This showed that those made of paraffin wax, the most common type, released potentially harmful amounts of chemicals such as toluene and benzene.